I have a similar issue, but instead of becoming anxious I become zombie-ish. My husband and I both travel occasionally for work. When I'm the one traveling I'm fine. But when he's traveling it's hard for me to function at home. I stare at the TV or computer for hours, I do not leave the house, I don't eat, I stim, I become lost in my thoughts. When he returns I don't snap out of it right away - the coma lingers for a day or two before I am able to return to normal.
I'm not sure what it is exactly. I don't miss him that much - it's only for a few days. It's more like I miss the routine we have together, and without him I have no routine.
_________________
Aspie score 138 of 200
Non-autistic score 70 of 200